The experts will be watching more intently when Apple announces the prices of its the colorful smartphone

"There's been a thorough leaking of Apple's most likely plans," said Ezra Gottheil, an analyst with Technology Business Research (TBI), on what Apple will unveil later today at an event on its Cupertino, Calif., campus. "But even without the leaks, there's not a whole lot of places to take the iPhone."

Six experts from six different research firms agreed that there would be few surprises from Apple, in large part because of the way supposedly secret details are leaked via the global sieve made up of Asian parts suppliers and uber-aggressive bloggers.

"We'll see a lower-cost iPhone, in addition to the new flagship model," said Kevin Restivo, an IDC analyst, in an interview.

"No epiphanies here," admitted Charles Golvin of Forrester. "There will be an iPhone 5s that will be to the 5 what the 4S and 3GS were to the 4 and 3G, respectively: Same industrial design, new processor to boost performance, improvements to the imaging experience, apparently growing color options, plus some form of biometric in place of the unlock swipe."

All the analysts bet Apple will host a double bill by unwrapping not only the annual upgrade to what Restivo called the "flagship," but also a first-ever lower-priced iPhone.

Pundits have labeled the flagship as the iPhone 5s (a nod to the iPhone 4S that followed the iPhone 4 in 2011) and the cheaper model the iPhone 5c, with the C possibly standing for "color," since the device is expected to be available in at least five colors, some of them reminiscent of those in the rainbow-themed logo Apple ditched in 1998.

Because the iPhone 5s will likely feature the same exterior design as last year's iPhone 5 -- Apple typically refreshes every two years -- the analysts' attention will be squarely on the iPhone 5c.

That attention will be drawn not to the specifications of the lower-cost model -- or the number of colors -- but to its price. It's the cost, one of the few details that hasn't leaked, that will determine their appraisals of what will arguably be Apple's biggest strategic move in smartphones since it rolled out the original iPhone six years ago.

"It all hinges on what the iPhone 5c is priced at," said Restivo. "It has to create the lust for the newer model that it's done for the flagship. Apple has always succeeded by selling the latest and greatest. Even in emerging markets, where people would be expected to make the compromise [of buying older iPhones at lower prices], that's more important than Apple once thought."

The iPhone 5c will be a departure for Apple: It has never shipped more than one model each year. But a hard charge by Samsung and the onslaught of countless cheaper Android models from other phone makers have erased significant portions of the iPhone's global market share. Rather than continue to rely on selling older models at cheaper prices, its strategy for several years, Apple needs an all-new lower-priced iPhone to maintain growth and profitability -- to please Wall Street, which has hammered Apple's stock in the last 12 months -- by broadening the potential pool of buyers.

Other experts have argued that Apple needs a cheaper iPhone, one that can compete in the huge swaths of the world where carrier subsidies are rare or non-existent, to maintain its market share so that developers remain committed to the app ecosystem.

Apple must walk a fine line, everyone agreed: Price the iPhone 5c too low and it will cannibalize sales of the iPhone 5s flagship in regions like the U.S., Western Europe and Japan. Price it too high and it won't kick-start sales in places like China, India and Brazil, where ultra-cheap Android smartphones have grabbed large chunks of market share.